1. Field of the Invention
The invention relates to a method, as well as to an apparatus for the production and treatment of a material web, and more particularly to a method and an apparatus for the production and treatment of a paper or cardboard web.
2. Description of the Related Art
A material web may be calendered in an off-line operation, for example, in the production of SC-A papers. The material web, which is calendered in an off-line operation for the production of SC-A papers, normally includes the following steps:    Drying of SC base paper to a low moisture content, for example to 2.5%, at the end of the dryer section of the respective paper machine.    High intensity moisturizing of the material web to a high moisture content—for example to 9.7%—by means of a moisturizing unit after the dryer section.    Winding of the material web at high moisture at the end of the paper machine    Unwinding of the highly moistened reel spool in the calender    Calendering    Winding of the calendered paper.The quality of calendered paper (gloss, smoothness) increases with increasing moisture in the base paper in the calender unwind and with increasing temperature and line force in the area of the calender rolls. A problem with calenders is that they are operated at their limits with regard to the temperature and the line force in the area of the calender rolls, thereby creating the danger of destruction and a relatively high wear and tear rate, as well as related low life spans of the roll covers.
Another problem is that, if a certain moisture content is exceeded after the moistener following the paper machine, considerable winding defects occur in the paper that is wound by the paper machine, resulting in increased waste as well as reduced runability and reduced capacity problems at the calender.
The remoistening that has hitherto been provided, as standard in off-line production of SC papers, was to prevent moisture from penetrating through the entire web, thereby providing moisture only to the top and bottom sides of the material web. Otherwise the web could be simply run at a higher moisture content coming from the dryer section, and could be wound without subsequent moistening.
During the storage, at the end of the paper machine, of the base paper that was wound while moist, a kind of “ripening” occurs in the reel spool. This is necessary to achieve the desired quality in the calendered finished product. In conventional paper machines, which are utilized in the manufacture of SC papers in on-line operation, gloss and smoothness are produced with paper that is not remoistened.